Polyalkylated oligoalkylenepolyamines are useful as ligands in a variety of chemical transformations, e.g., as ligands for metal species in homogeneous atom transfer radical polymerization reactions, and have a variety of other uses, e.g., as anti-wear lubrication additives. Polyalkylated polyamine ligands, such as N,N,N′,N″,N″-pentaethyl-diethylenetriamine (“PEDETA”) or N,N,N′,N′-tetraethylethylenediamine (“TEEDA”), are also useful as ligands in the production of tetradecachlorocyclohexasilane dianions from trichlorosilane. Polyalkylated oligoalkylenepolyamines have commonly been prepared through reaction of polyamine compounds (e.g., dialkylenetriamines) with an alkyl halide. This reaction, however, has been reported to suffer from low yields and/or prolonged reaction times. In many instances, difficulties in inducing the reaction to achieve complete alkylation have been experienced, leading to product mixtures containing substantial amounts of partially alkylated products. Previous attempts to alkylate alkylenepolyamines with 1-chloro-n-alkanes by conventional procedures have resulted in low substitution yield, even after prolonged reaction times. The low conversion rates in such attempted reactions have been attributed to the low reactivity of the alkyl chloride.